Japanese Unexamined Patent Publication No. H6-510968 discloses a brake pressure controller which includes a suction path for drawing out brake fluid in a master cylinder through use of a hydraulic pump to supply such brake fluid to the wheel cylinders. In addition, a main path connects the master cylinder and the wheel cylinders, a normally closed suction valve is provided on the suction path and a normally open shut-off valve is provided on the main path.
This controller performs traction control in which the suction valve is opened and the shut-off valve is closed regardless of the operation of a brake pedal, and the hydraulic pump is operated to supply brake fluid in the master cylinder to the wheel cylinders. To perform quick pressurization using the hydraulic pump at the beginning of the control operation, it is possible to either use a very large hydraulic pump or use a hydraulic pump for charging in addition to the hydraulic pump for pressurization. In either case, the size of the controller is significantly increased as is the cost of the overall apparatus.
In light of the foregoing, a need exists for a brake pressure controller in which the above-described problem is addressed.
More particularly, a need exists for a brake pressure controller which is able to effect quick pressurization at the beginning of traction control operation without the need for a larger hydraulic pump or a second hydraulic pump.